Tag Archives: Comprehensive Nuclear Test Ban Treaty (CTBT)

The Cracks on the Nuclear Runit Tomb

Excerpts from the US Department of Energy Report on the Nuclear Runit Dome

The Runit Dome is a containment structure on Runit Island, located on Enewetak Atoll.  Enewetak Atoll is a former U.S. atmospheric nuclear weapons test site located approximately 2,300 miles west of Hawaii in the northwest Pacific Ocean. The Runit Dome,  which was built in the late 1970s, contains over 100,000 cubic yards of contaminated soil and  debris [from the US nuclear weapons testing] that were encapsulated in concrete inside an unlined nuclear test crater, the Cactus Crater, on the north end of Runit Island. The site has remained a concern to the people of Enewetak. 

The Runit Dome is not in any immediate danger of collapse or failure, and the exterior concrete covering the containment structure is still serving its intended purpose, effectively reducing the natural erosion of the waste pile below by wind and water. Visual surveys of the exterior  concrete of the Cactus Crater containment structure have revealed the presence of cracks and spalls in the concrete cap. However, these cracks and spalls in the exterior concrete cap do not form sites for external or internal radiation exposure that impact or endanger human health or
the environment, or wildlife.

DOE has performed preventative maintenance on exterior surfaces of the containment structure, which will aid in the determination of any changes that
may occur in the condition of the concrete in the future. Any concerns about the imminent failure or collapse of the structure are unfounded.

The main safety concern to humans associated with leakage of radioactive waste from the Cactus Crater containment structure is the uptake of fallout radioactivity in marine foods. There are no data to suggest that the Cactus Crater containment structure, or more specifically, the radioactive material encapsulated in Cactus Crater, is currently having a measurable adverse effect on the surrounding environment or on the health of the people of Enewetak. However, DOE is in the process of establishing a groundwater radiochemical analysis program that is designed to provide scientifically substantiated data that can be used to determine what, if any, effects the dome contents are having, or will have, on the surrounding environment now
and in the future.

Long-term trends in the concentration of Pu in lagoon waters derived from retrospective analysis of a coral core collected off Runit Island show levels of Pu in lagoon waters are systematically decreasing. These data provide compelling evidence that the construction of the Runit Dome has had, and continues to have, a negligible impact on the wider marine environment….

The Cactus Crater containment structure remains vulnerable to wave driven over wash and flooding caused by storm surge and potential effects of sea level rise… It is
anticipated that any measured or modeled effects of storm events may help provide a better understanding of the long-term consequences of sea-level rise on mass-transport of dome derived radionuclides.

Sniffing the Earth for Nuclear Exposions

Australia’s infrasound station “IS03” in Davis Base, Antarctica, is one of nearly 300 certified stations of the Comprehensive Nuclear Test Ban Treaty (CTBT) Organization monitoring system, feeling and sniffing the Earth for any signs of a nuclear explosion. The global system will comprise 337 facilities when complete.  “The monitoring stations in Australia cover a large expanse of the Southern hemisphere. They are strategically positioned to contribute significantly to the International Monitoring System (IMS) detection and location capability. All six nuclear tests by North Korea were clearly detected by Australia’s IMS seismic stations,” Zerbo said.

“Australia ranks third among countries hosting the largest number of monitoring facilities.  It covers all four technologies used for nuclear test detection. Some of the stations are located in particularly remote and inaccessible areas of the Earth, such as Antarctica. This has been a 20 year-long joint effort by CTBTO and Australia and is truly an extraordinary achievement,” Zerbo said.

The CTBTO’s global monitoring network captures four types of data: vibrations through the ground and in water – seismic and hydroacoustic; sound beyond the range of the human ear and detection of radioactive particles – infrasound and radionuclide.

The network guards against violations of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) banning nuclear explosions by everyone, everywhere: in the atmosphere, underwater and underground.  The global network detects nuclear tests with high reliability. For example, on 3 September 2017, over 100 stations in the network detected and alerted Member States to North Korea’s last announced nuclear test.

Excerpts from Comprehensive Nuclear Test  Ban Treaty Organization (CTBTO), Australia Completes Its Monitoring Stations in the Global Network to Detect Nuclear Tests, Nov 18, 2018, 15:45 ET